Radiation testing is an important part of product testing that is required for devices that will be used in high-radiation environments. These high-radiation environments may include, for example, outer space and high-altitude flight areas, regions around nuclear reactors and particle accelerators, etc. Particle accelerators are typically used to perform radiation testing. A radiation test customers may request thousands of radiation exposures across dozens of different radiation environments for each device under test. The particle accelerator is usually set to provide a fixed known output and the actual radiation environment provided is controlled by attenuating that output by inserting a beam diffuser in front of the output of the particle accelerator. There are two other ways to control the output of a particle accelerator, by adjusting the tuning of the particle accelerator (commonly referred to as the “accelerator's tune”) and by changing the distance between the output of the particle accelerator and the device under test. However, the accurate adjustment to a new output level of the particle accelerator output may require several hours of time. This type of beam output adjustment is not practical for testing involving a number of different type of tests. Furthermore, certain testing may require radiation at levels ranging over several orders of magnitude which requires a test cell having a test track (for a movable platform to hold the device under test) which is longer than practical (e.g., on the order of one thousand feet or so).
The beam diffuser used on the output of the particle accelerator is typically a metallic (e.g., aluminum or tantalum) plate of a predetermined thickness affixed directly over the output. By using a number of different plates, each having a different predetermined thickness, various different radiation environments can be provided. However, the time required to change the configuration between radiation environments can be significant, requiring several minutes for an operator to turn the particle accelerator to an off-state, break the safety interlocks on the test cell door, enter the test cell, manually replace the plate on the front end of the accelerator, reset the safety interlocks on the test cell door, exit the test cell, and turn the particle accelerator back to an on-state. The use of beam diffusers is more practical than adjusting the particle accelerator output or by changing the position of the device under test, but still can add a significant amount of time for the complete test procedure due to the time required for each plate change.
Accordingly, there is a need for an apparatus and method which overcomes the problems recited above.